J. Org. C h e m . 1994,59, 6133-6135
6133
Asymmetric Synthesis of Isoindoline and Isoquinoline Derivatives Using Nickel(0)-Catalyzed[2 2 21 Cocyclization
+ +
Yoshihiro Sato, Toyoki Nishimata, and Miwako Mori* Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060, J a p a n Received May 4, 1994@
+ +
Summary: A nickel(0)-catalyzed asymmetric 12 2 21 cocyclization has been realized for the first time, giving the isoindoline 16a in 73% ee (52% yield) and the isoquinoline 17b in 54% ee (62% yield), respectively.
Scheme 1
9'
+ +
The [2 2 21 cocyclization of a,w-diynes and alkynes in the presence of a transition metal complex is valuable in modern synthetic organic chemistry because regio- and stereospecific C-C bond formation occurs.1p2 Recently, nickel(0)-promoted [2 2 21 cocyclization was rep ~ r t e d .The ~ reaction mechanism was not clear, but it was speculated that formation of a nickelacyclopentadiene 4 as an intermediate by oxidative cyclization of the two alkynes was involved (Scheme l L 3 s 4 If the nickelacyclopentadiene 4 is truly an intermediate and then the alkyne 2 is inserted into 4, the reaction should proceed using a catalytic amount of a low valent nickel complex analogous to a rhodium-catalyzed cocyclization.2 Most analgesics such as morphine have chiral carbon centers a t the benzylic position. For the construction of such center^,^^^ we planned to use a nickel(0)-catalyzed [2 2 21 cocyclization of a,o-diynes. Our basic strategy for the catalytic asymmetric synthesis of isoindoline and isoquinoline derivatives is shown in Scheme 2, which involves conceptually new enantiotopic group selective formation of nickelacyclopentadiene. According to the above-mentioned speculations, the two triple bonds of the triyne 5 (one of them is a straight-chain alkyne, and the other is one of two branched alkynes) react with zero valent nickel complex coordinated with a chiral
1
3
2
a
+ +
+ +
@Abstractpublished in Advance ACSAbstracts, September 15,1994. (1)(a) Vollhardt, K.P. C. Angew. Chem., Znt. Ed. Engl. 1984, 23, 539 and references cited therein. (b) Vollhardt, K. P. C. Acc. Chem. Res. 1977, 10, 1. (2)(a)Grigg, R.; Scott, R.; Stevenson, P. J.Chem. SOC., Perkin Trans. 1 1988, 1357.(b) Grigg, R.; Scott, R.; Stevenson, P. Tetrahedron Lett. 1982,23, 2691.(c)Neeson, S. J.; Stevenson, P. J. Tetrahedron 1989, 45, 6239.(d) Neeson, S.J.; Stevenson, P. J. Tetrahedron Lett. 1988, 29, 813. (3)(a) Bhatarah, P.;Smith, E. H. J. Chem. SOC.,Perkin Trans. 1 1992, 2163. (b) Bhatarah, P.;Smith, E. H. J. Chem. SOC., Chem. Commun. 1991, 277. (c) Bhatarah, P.;Smith, E. H. J. Chem. SOC., Perkin Trans. 1 1990, 2603. (4)It was reported that the reaction of a hepta-l,&diyne and a monosubstituted alkyne using a stoichiometric amount of nickel(0) complex afforded indan derivatives in good to moderate yields. However, it was also reported that the reaction using a catalytic amount of nickel(0) complex (20mol %) went to 40-50% completion. See ref 3c. (5)For some elegant examples of the catalytic asymmetric construction of chiral carbon centers at the benzylic position, see: (a)Noyori, R.; Ohta, M.; Hsiao, Y.; Kitamura, M.; Ohta, T.; Takaya, H. J. Am. Chem. SOC.1986,108, 7117.(b) Kitamura, M.; Hisao, Y.; Noyori, R.; (c) Kitamura, M.; Hsiao, Takaya, H. Tetrahedron Lett. 1987,28,4829. Y.; Ohta, M.; Tsukamoto, M.; Ohta, T.; Takaya, H.; Noyori, R. J . Org. Chem. 1994, 59, 297. (d) Takemoto, T.; Sodeoka, M.; Sasai, H.; 1998,115, 8477. Shibasaki, M. J.Am. Chem. SOC. (6)For a n elegant example of the diastereoselective alkylation of tetrahydroisoquinolines,see: (a) Meyers, A. I.; Fuents, L. M. J. Am. Chem. SOC. 1988, 105, 117.(b) Meyers, A. I.; Dickman, D. A,; Bailey, 1985, 107, 7974.(c) Meyers, A. I.; Bailey, T. T. R. J.Am. Chem. SOC. R. J.O g . Chem. 1986,51,872.(d) Meyers, A. I.; Dickman, D. A.; Boes, M. Tetrahedron 1987,43, 5095.(e) Meyers, A. I.; Boes, M.; Dickman, D. A. Org. Synth. 1989, 67, 60. (0Meyers, A. I.; Guiles, J.; Warmus, J. S.; Gonzalez, M. A. Tetrahedron Lett. 1991, 32, 5505. For other examples of asymmetric synthesis of optically active alkaloids based on stoichiometric chirality transfer, see ref 5c.
N
i
4
Scheme 2
5 : X=N, C, 0 etc.
6'
F
n
6
I
T
\
I"
)R
L
n
*
N
R+ 2
II
xi 4nantiotopic group ~ selection
4 R'
ligand to give the nickelacyclopentadiene I1 in an optically active form via I. The insertion of alkyne 2 into I1 would afford the nickelacycloheptatriene III. Then reductive elimination would proceed, which provides the heterocycle 6 or 6' having the benzylic chiral carbon center. Thus, a catalytic asymmetric synthesis of isoindoline and isoquinoline would be realized. In order to realize the nickel-catalyzed asymmetric synthesis according to our strategy, use of acetylene or disubstituted alkynes 2 is ne~essary.',~We examined the 2 21 cocyclization of diyne 7a and gaseous [2 acetylene. A balloon filled with gaseous acetylene was connected a t the reaction vessel containing a THF solution of 7a and 20 mol % nickel(0) complex, generated
+ +
(7)The nickel catalyzed [2+ 2 + 21 cocyclization of diyne 7b and propargyl alcohol in the presence of 10 mol % nickel(0) complex, generated from Ni(acac)n (10mol %) and DIBAH (2equiv to Ni) in the presence of PPh, (40 mol %), smoothly proceeded to give an inseparable mixture of isoquinoline derivatives 23 (RI = H, R2 = CHzOH and RI = CHzOH, R2 = H) (1:2,the regioisomers of the hydroxymethyl group on the aromatic ring) in 72% yield.
0022-3263/94/1959-6133$04.50/00 1994 American Chemical Society
6134 J. Org. Chem., Vol.59,No.21, 1994
Communications
Scheme 3
Scheme S
20 mol % Ni(O)-PPh,, THF, 23 "C, HCZCH 12 hr
*NTs
' e
-
8 mol Yo Ni(cod)z 20 mol % Ligand
T"S /
R' 12a: R=Bn, R'-H 13a: R=Tr, R'=TMS 14a: R=Tr, R'=H
mol Ly30Ni(O)-PPh3, HCECH %
/eNTs
THF, 23 OC, 18 hr
Scheme 4= +n NH
TMS
l l a : n=l (96%) 11b: n=2 (78%)
c1 +n
NTr
TMS+{
a
13a: n=l (68%) 13b: n-2 (60%)
ph3c
TMS
of 13a and 14a
run substrate
ligand
n
1 2
12a: n=l (2 steps 44%) 12b: n=2 (2steps 50%)
d
Table 1. Catalytic Asymmetric [2 + 2 + 21 Cocyclization
